1. Field of the Invention
This invention concerns a building form and system for forming hardenable material such as concrete. More particularly, it is concerned with a method, stiffback and building form system which permits the stiffback to be used as a penetratable building form.
2. Description of the Prior Art
Building forms are widely used to form walls, foundations and the like of hardenable material such as concrete. Such building forms may be of different materials such as wood or foam, but these typically lack durability for repeated usage. Thus, reusable building forms are more often of metal, such as aluminum which is lightweight and durable. In constructing foundations out of such building forms, panels are typically interconnected in side-by-side relationship to comprise a forming wall, and another such forming wall is opposed thereto to receive the concrete or other flowable, hardenable and typically cementations material therebetween. To provide rigidity, especially for greater depths of material, intermediate cross-beams may be provided on the back side of the building form panels making up the forming walls.
Because of the great weight of the concrete material received between the forming walls, stiffbacks are employed behind the panels to provide support and resist deflection of the panels outwardly from the material receiving area. The stiffbacks are positioned in an upright orientation behind the panels at selected intervals and may be connected to the back of the forming panels by bolting or similar fastening means. To provide further resistance to separation, tapered connecting rods penetrate through openings drilled in the panels of opposing walls and pass through the material receiving region between the opposing panels to tie the building forms of the opposing forming walls together against separation.
While this system and method is useful, it is also expensive as drilling a hole through a building form renders it unsuitable for further use. Unless the hole is repaired by expensive welding due to the usually aluminum material, the entire panel must be replaced. Moreover, in addition to the panels which spanned the entire width of the wall, additional stiffback members were required to reinforce the wall. Consequently, the resulting total cost of materials of a wall including both stiffbacks and panels is greater than the panel alone.
There has thus developed a need for an economical building form system which can be readily erected and used with existing ancillary equipment.